ChatID is a type alias for an Ed25519 signature key.

2 files changed, 37 insertions, 4 deletions

diff --git a/src/Data/Tox/Msg.hs b/src/Data/Tox/Msg.hs
index d42b092b..e8c26a56 100644
--- a/src/Data/Tox/Msg.hs
+++ b/src/Data/Tox/Msg.hs
@@ -10,6 +10,9 @@
 {-# LANGUAGE TypeFamilies               #-}
 module Data.Tox.Msg where
 
+import Crypto.Error
+import qualified Crypto.PubKey.Ed25519 as Ed25519
+import Data.ByteArray             as BA
 import Data.ByteString            as B
 import Data.Dependent.Sum
 import Data.Functor.Contravariant
@@ -234,8 +237,28 @@ lossyness m = case msgbyte m of
       | otherwise            -> Lossless
 
 
-newtype ChatID = ChatID Nonce32
- deriving (Eq,Show,Serialize,Sized)
+newtype ChatID = ChatID Ed25519.PublicKey
+ deriving Eq
+
+instance Sized ChatID where size = ConstSize 32
+
+instance Serialize ChatID where
+    get = do
+        bs <- getBytes 32
+        case Ed25519.publicKey bs of
+            CryptoPassed ed -> return $ ChatID ed
+            CryptoFailed e -> fail (show e)
+    put (ChatID ed) = putByteString $ BA.convert ed
+
+instance Read ChatID where
+    readsPrec _ s
+        | Right bs <- parseToken32 s
+        , CryptoPassed ed <- Ed25519.publicKey bs
+                    = [ (ChatID ed, Prelude.drop 43 s) ]
+        | otherwise = []
+
+instance Show ChatID where
+    show (ChatID ed) = showToken32 ed
 
 data InviteType = GroupInvite { groupName :: Text }
                 | AccptedInvite
diff --git a/src/Network/Tox/NodeId.hs b/src/Network/Tox/NodeId.hs
index 97faa942..56ddf03c 100644
--- a/src/Network/Tox/NodeId.hs
+++ b/src/Network/Tox/NodeId.hs
@@ -37,6 +37,8 @@ module Network.Tox.NodeId
     , verifyChecksum
     , ToxContact(..)
     , ToxProgress(..)
+    , parseToken32
+    , showToken32
     ) where
 
 import Control.Applicative
@@ -166,18 +168,26 @@ nmtoken64 True  '+' = '.'
 nmtoken64 True  '/' = '-'
 nmtoken64 _     c   = c
 
+-- | Parse 43-digit base64 token into 32-byte bytestring.
+parseToken32 :: String -> Either String ByteString
+parseToken32 str = fmap (BA.drop 1) $ Base64.decode $ C8.pack $ 'A':map (nmtoken64 False) (take 43 str)
+
+-- | Encode 32-byte bytestring as 43-digit base64 token.
+showToken32 :: ByteArrayAccess bin => bin -> String
+showToken32 bs = map (nmtoken64 True) $ C8.unpack $ BA.drop 1 $ Base64.encode $ BA.cons 0 $ BA.convert bs
+
 instance Read NodeId where
     readsPrec _ str
         | (bs,_) <- Base16.decode (C8.pack $ take 64 str)
         , CryptoPassed pub <- publicKey bs -- B.length bs == 32
                     = [ (key2id pub, drop (2 * B.length bs) str) ]
-        | Right bs <- fmap (BA.drop 1) $ Base64.decode $ C8.pack $ 'A':map (nmtoken64 False) (take 43 str)
+        | Right bs <- parseToken32 str
         , CryptoPassed pub <- publicKey bs -- B.length bs == 32
                     = [ (key2id pub, drop 43 str) ]
         | otherwise = []
 
 instance Show NodeId where
-    show nid = map (nmtoken64 True) $ C8.unpack $ BA.drop 1 $ Base64.encode $ BA.cons 0 $ BA.convert $ id2key nid
+    show nid = showToken32 $ id2key nid
 
 instance S.Serialize NodeId where
     get = key2id <$> getPublicKey